Historical Background and Book
Contents
13
waterfall interpretation. How the contributions of the microcirculation to
total peripheral resistance in its control of cardiac output are explained.
The
capillary circulation,
for
its
vast
networking
and
exchange
environment is of utmost importance in terms of meeting the metabolic
demand of the supplying tissues. The aspects of diffusion and cellular
transports are of critical importance.
Thus, the design of the arterial tree is to facilitate pulse transmission
to vascular beds. These latter are discussed in detail for their importance
in both basic and clinical situations.
Pulse pressure and flow remain
pulsatile even in the microcirculation, albeit to a much more reduced
amplitudes. The pulsatility facilitates capillary exchanges.
The final chapter deals with aspects of experimental methods,
instrumentation and devices that are widely used for hemodynamic
measurements.
Clinically useful methods and instruments for invasive
and noninvasive determination of blood pressure flow, and vessel
dimensions are first described. This begins with the commonly used
noninvasive
methods,
such
as
auscultatory
method,
the
sphygmomanometer cuff method and tonometry.
Invasive
blood
pressure
measurement
system such as catheter-pressure
transducer
combination is also evaluated in terms
of
its frequency response.
Blood flow measurement with both electromagnetic flowmeter and
Doppler ultrasonic method are described, as well as the technique of
therrnodilution measurement of cardiac output.
The combination of
Doppler echocardiography and intravascular imaging devices now afford
simultaneous flow velocity and lumen diameter measurements.
The aspect of cardiac assist device to aid the failing heart is well
appreciated with the introduction of the intra-aortic balloon pump. Our
experience with this in-series cardiac assist device is illustrated in terms
of hemodynamic function. The dynamics of the assisted circulation is
examined in terms of different modes of mechanical assistance.
The overall function of the dynamics of the vascular system depends
not only on the anatomical structure of the individual vessels, but also on
their multi-faceted functional interaction with neighboring and distant
vessels. This will become apparent to the readers from the contents of
this book.
